This crab hides under
sand or mud during the day, coming out at dusk to hunt for small fish and
other animal matter. Adult males have blue markings on their shells and
long pincers whereas females are dull green. Extensively caught for food,
they, however, do not live long once out of the water and deteriorate rapidly.
(Width up to 20cm).

Their shells can frequently be found on the shore. Most are not dead crabs
but merely the moults. Crustaceans moult, i.e., change and replace their
shell when they grow larger. Moults are easily recognised because they are
very light, the inner layers have no flesh, the eyes are transparent, and
there is no bad odour. Newly moulted crabs have soft shells and are popular
food items in the Americas.